Internet users' activities are critical to the development and success of Web 2.0 systems, such as online communities. Within the community's participation, knowledge sharing, and communications, users may conduct aggressive behaviors that would have a negative impact on that online community. This study investigates factors that affect Chinese users' aggression intention in online communities. Research findings show that online aggression can be inhibited by internal deterrents of face saving and moral beliefs, which may be enhanced through implementation of consequences from an effective community policy and peer pressure among community members. Differences in the effects of the deterrence measures exist between younger and older users. This paper contributes theoretically and empirically to Web 2.0 research and has practical implications for virtual community management.